Converso (Spanish and Portuguese for "a convert", from Latin conversus, "converted, turned around") and its feminine form conversa referred to Jews or Muslims or the descendants of Jews or Muslims who had converted to Catholicism in Spain and Portugal, particularly during the 14th century and 15th century.
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Conversos were apparently subject to harassment from both the community they were leaving and that they were joining. Both Christians and Jews called them tornadizo (renegade), and laws were passed during the reigns of Jaime I, Alfonso X and Juan I forbidding the use of this epithet. This was part of a larger pattern of royal protection, laws also being promulgated to protect their property, forbid attempts to reconvert them, and regulating the behavior of the conversos themselves, preventing their cohabitation or even dining with Jews, lest they reconvert. However, they did not enjoy legal equality, Alfonso VII prohibiting the "recently converted" from holding office in Toledo, and they had both supporters and bitter opponents within the Christian secular and religious leadership. Conversos could be found in various roles within the Iberian kingdoms, from Bishop to royal mistress, showing a degree of general acceptance, yet they would become targets of occasional pogroms and of the Spanish Inquisition and Portuguese Inquisition.
While pure blood (so-called limpieza de sangre) would come to be placed at a premium, particularly among the nobility, in a 15th century defense of conversos Bishop Lope de Barrientos would list what Roth calls "a veritable 'Who's Who' of Spanish nobility" as having converso members or being of converso descent and would point out that given the near-universal conversion of Iberian Jews during Visigothic times, (quoting Roth) "who among the Christians of Spain could be certain that he is not a descendant of those conversos?"

Morisco for New Christians of Moorish origin. The term morisco may also refer to Crypto-Muslims, i.e. those who secretly continued to practice Islam.
Marrano for New Christians of Jewish origin. The term marrano may also refer to Crypto-Jews, i.e. those who secretly continued to practice Judaism.